Processes for sterilizing and deaerating fruit juices are well known; Sterilization is performed in order to eliminate problems linked to the development of microorganisms, and deaeration is aimed at reducing the level of dissolved oxygen in the fruit juice which is treated.
When manufacturing shelf-stable fruit juices, the reduction of the dissolved oxygen level is desirable in order to minimize the chemical oxidation processes that would otherwise develop in the fruit juice during the subsequent storage period, making it unfit for human consumption.
As disclosed in the European patent application EP 01 008 33-A, as well as in the French patent application FR 2 488 785-A, the known deaeration processes are carried out in vacuum conditions and are characterized by the elevated temperatures needed, i.e. above 50.degree. C., in order to ensure a good efficiency in the process.
Although these processes allow to reach very low levels of dissolved oxygen in the deaereated fruit juices, they are not fully satisfactory; indeed, the use of high temperatures is prejudicial to an optimal conservation of the different volatile components of the treated fruit juice throughout the deaeration and, therefore, to the conservation of the aroma and taste of the fresh fruit juice.
It is an object of the present invention to provide an efficient deaeration process to be applied to the manufacture of shelf stable fruit juices, said process being performed at a temperature such as to avoid damaging the volatile components and vitamins of the treated fruit juice.